Effectiveness and safety of anakinra in gout patients with stage 4–5 chronic kidney disease or kidney transplantation: A multicentre, retrospective study

Immune-inflammatory process in nephrolithiasis: A bibliometric analysis (2000-2023)

The research on the mechanism of nephrolithiasis formation is of great importance due to the fact that the high incidence and recurrence rate of nephrolithiasis bring considerable economic burdens to patients and society. As an important component in the nephrolithiasis formation process, the immune-inflammatory process has been gradually valued by researchers in recent years. In this study, articles related to the immune-inflammatory process of nephrolithiasis published since 2000 were retrieved based on the Web of Science (WoS) database. Eventually, a total of 370 articles were selected for subsequent analyses. Besides, VOSviewer, CiteSpace, and Bibliometrix were employed to quantitatively analyze and visualize the data. The number of articles related to the immune-inflammatory process of nephrolithiasis has increased rapidly in the last five years. From the country level, most articles were contributed by China (n = 140) and the United States (n = 99) contributed the most documents. From the institution level, University of Florida (n = 36) and Nagoya City University (n = 21) had the most articles. From the journal level, Journal of Urology and Urolithiasis published the most articles in this field. Keywords mainly included inflammation, oxidative stress, calcium oxalate, osteopontin, and hyperoxaluria, which represented the research directions in this field. The most productive author was Khan SR (n = 33), whose articles obtained the highest number of citations (2086 times). These efforts may help researchers understand the current progress and status of research on the immune-inflammatory process of nephrolithiasis and identify future research hotspots and directions.

Managing Gout in Patients with Metabolic Syndrome

Gout is characterized by monosodium urate (MSU) crystal deposition secondary to hyperuricemia. Gout is associated with metabolic syndrome (MetS) and its related comorbid conditions such as cardiovascular disease (CVD). Major advances have been made in the comprehension of the link between MetS and gout. Despite observational studies suggesting an association between MetS-related conditions and hyperuricemia, there is no proof of causality. Most studies using Mendelian randomization did not find hyperuricemia as a causal factor for MetS-related conditions. In contrast, these conditions were found associated with hyperuricemia, which suggests a reverse causality. Among patients with gout, this high CVD risk profile implies the need for systematic screening for MetS-related conditions. Most international guidelines recommend systematic screening for and care of CVD and related risk factors in patients with gout. Some anti-hypertensive agents, such as losartan and calcium channel blockers, are able to decrease serum urate (SU) levels. However, there are potential interactions between gout management therapies and the treatment of metabolic diseases. Some data suggest that anti-inflammatory drugs used for gout flare treatment, such as colchicine or canakinumab, might have benefits for CVD. Regarding the impact of urate-lowering therapies on CVD risk, recent studies found a similar CVD safety profile for allopurinol and febuxostat. Finally, sodium-glucose cotransporter-2 inhibitors are promising for gout because of their ability to decrease SU levels and risk of recurrent flares. In this review, we focus on the clinical challenge of managing MetS in patients with gout, particularly older patients with co-medications.

Acute kidney injury in severe alcohol-associated hepatitis treated with anakinra plus zinc or prednisone

BACKGROUND AND AIMS

In a recent trial, patients with severe alcohol-associated hepatitis treated with anakinra plus zinc (A+Z) had lower survival and higher acute kidney injury (AKI) rates versus prednisone (PRED). We characterize the clinical factors and potential mechanisms associated with AKI development in that trial.

APPROACH AND RESULTS

Data from 147 participants in a multicenter randomized clinical trial (74 A+Z, 73 PRED) were analyzed. AKI, AKI phenotypes, and kidney injury biomarkers were compared between participants who did/did not develop AKI in the 2 treatment arms. Multivariable competing risk analyses were performed to identify baseline risk factors for incident AKI, with death treated as a competing event. Risk factors considered were age, sex, mean arterial pressure, white blood cell count, albumin, MELD, ascites, HE, and treatment arm. At baseline, no participants had AKI; 33% (n=49) developed AKI during follow-up. AKI incidence was higher in A+Z than in PRED (45% [n=33] versus 22% [n=16], p =0.001). AKI phenotypes were similar between the 2 treatment arms ( p =0.361), but peak AKI severity was greater in A+Z than PRED (stage 3 n=21 [63.6%] vs. n=8 [50.0%], p =0.035). At baseline, urine-neutrophil-gelatinase-associated lipocalin levels were similar between participants who developed AKI in both treatment arms ( p =0.319). However, day 7 and 14 urine-neutrophil-gelatinase-associated lipocalin levels were significantly elevated in participants treated with A+Z who developed AKI versus participants treated with PRED who developed AKI ( p =0.002 and 0.032, respectively). On multivariable competing risk analysis, only A+Z was independently associated with incident AKI (subdistribution hazard ratio 2.35, p =0.005).

CONCLUSIONS

AKI occurred more frequently and was more severe in participants treated with A+Z. A+Z-treated participants with AKI had higher urine-neutrophil-gelatinase-associated lipocalin, suggesting that A+Z maybe nephrotoxic in patients with severe alcohol-associated hepatitis.

Autoinflammatory diseases and the kidney

The kidney represents an important target of systemic inflammation. Its involvement in monogenic and multifactorial autoinflammatory diseases (AIDs) vary from peculiar and relatively frequent manifestations to some rare but severe features that may end up requiring transplantation. The pathogenetic background is also very heterogeneous ranging from amyloidosis to non-amyloid related damage rooted in inflammasome activation. Kidney involvement in monogenic and polygenic AIDs may present as renal amyloidosis, IgA nephropathy, and more rarely as various forms of glomerulonephritis (GN), namely segmental glomerulosclerosis, collapsing glomerulopathy, fibrillar, or membranoproliferative GN. Vascular disorders such as thrombosis or renal aneurysms and pseudoaneurysms may be encountered in patients with Behcet's disease. Patients with AIDs should be routinely assessed for renal involvement. Screening with urinalysis, serum creatinine, 24-h urinary protein, microhematuria, and imaging studies should be carried out for early diagnosis. Awareness of drug-induced nephrotoxicity, drug-drug interactions as well as addressing the issue of proper renal adjustment of drug doses deserve a special mention and should always be considered when dealing with patients affected by AIDs. Finally, we will explore the role of IL-1 inhibitors in AIDs patients with renal involvement. Targeting IL-1 may indeed have the potential to successfully manage kidney disease and improve long-term prognosis of AIDs patients.

The Hong Kong Society of Rheumatology consensus recommendations for the management of gout

Gout is one of the most common noncommunicable diseases in Hong Kong. Although effective treatment options are readily available, the management of gout in Hong Kong remains suboptimal. Like other countries, the treatment goal in Hong Kong usually focuses on relieving symptoms of gout but not treating the serum urate level to target. As a result, patients with gout continue to suffer from the debilitating arthritis, as well as the renal, metabolic, and cardiovascular complications associated with gout. The Hong Kong Society of Rheumatology spearheaded the development of these consensus recommendations through a Delphi exercise that involved rheumatologists, primary care physicians, and other specialists in Hong Kong. Recommendations on acute gout management, gout prophylaxis, treatment of hyperuricemia and its precautions, co-administration of non-gout medications with urate-lowering therapy, and lifestyle advice have been included. This paper serves as a reference guide to all healthcare providers who see patients who are at risk and are known to have this chronic but treatable condition.

Therapeutics in rheumatology and the kidney

The field of rheumatology has advanced significantly in recent years to provide rheumatologists with an extensive array of medications to combat rheumatic joint conditions. In contrast to an older era, when NSAIDs and other nephrotoxic agents were the mainstay of treatment, modern DMARDs vary considerably in their nephrotoxic potential and their use is not always precluded in populations with pre-existing chronic kidney disease (CKD). This review will explore in detail the safety and efficacy profiles of medications used to treat rheumatologic disease, specifically in the setting of CKD. Specifically, we discuss both traditional agents used, i.e. NSAIDs, CSs and conventional synthetic DMARDs, as well as novel biologic DMARDs and targeted synthetic DMARDs. Anti-gout prescribing in CKD is also reviewed. We aim to provide practical guidance to rheumatologists, nephrologists and general physicians when prescribing these medications in the setting of CKD.

Inflammation and kidney stones: cause and effect?

PURPOSE OF REVIEW

This short review is intended to highlight the potential role of inflammation as a key pathological driver, rather than a mere consequence, of nephrolithiasis. Although there is clearly a strong likelihood that the relationship is bidirectional, and that kidney stone-triggered inflammation can establish a vicious cycle of tissue injury and stone formation.

RECENT FINDINGS

These consist of data from both recent preclinical and clinical studies demonstrating the importance of inflammation in models of stone disease and in kidney tissue from patients with nephrolithiasis, and as a potential driver of disease recurrence and a suitable treatment target. In particular, the role of immune cells and their relationship to the NLRP3 inflammasome is becoming clearer, as well as the potential contribution to tissue injury and stone formation of the pro-inflammatory cytokines interleukin-1β and interleukin-18.

SUMMARY

This concept is not new and raises the possibility that targeting inflammation directly may prove to be a novel and suitable means of treatment for at least some types of kidney stone, and in certain clinical settings, both acutely and as prevention, especially in those patients experiencing recurrent stone episodes and/or who have a well defined metabolic cause such as uric acid or calcium oxalate stones.

Effectiveness and safety of anakinra in gouty arthritis: A case series and review of the literature

Background

Gout is the most common type of inflammatory arthritis. Nonsteroidal anti-inflammatory drugs, corticosteroids, and colchicine are the first-line agents, although they are contraindicated in many patients. Blockade of IL-1 with anakinra can be an alternative.

Objective

To present a case series of 10 difficult-to-treat gout patients treated with anakinra and perform a scoping review of the effectiveness and safety of anakinra in gout patients.

Methods

A total of 1,519 citations were screened. The reviewers ran a two-stage screening process by title/abstract and full-text reading. Thirty-eight articles finally met the selection criteria and were included for data extraction and synthesis. Experience in difficult-to treat and complex clinical scenarios, such as active infection, hemodialysis, and transplantation, were specifically described.

Results

The study sample comprised 551 patients, from whom 648 flares were finally analyzed. The mean age was 57.9 years, and 82.9% were men. The clinical presentation was polyarticular in 47.5% and tophaceous in 66.9%. Sixty-five patients with an active infection, 41 transplanted patients and 14 in haemodyalisis treated with anakinra are described. More than half of the patients had >1 associated comorbidity. Anakinra was effective both for flares (94%) and for long-term treatment (91%) and well tolerated. In the case of flares, 34 (6.7%) adverse effects were registered. Adverse events were more prevalent in long-term treatment.

Conclusion

Anakinra was effective and safe for management of gout flares in difficult-to-treat patients. It has been used in multiple complex scenarios, such as active infections, dialysis, transplantation, chronic kidney disease, and polyarticular gout. Anakinra has also proven effective as long-term treatment, although there are more concerns about its safety.

Gasdermins and pyroptosis in the kidney

Pyroptosis is a form of regulated cell death that is mediated by the membrane-targeting, pore-forming gasdermin family of proteins. Pyroptosis was initially described as a caspase 1- and inflammasome-dependent cell death pathway typified by the loss of membrane integrity and the secretion of cytokines such as IL-1β. However, gasdermins are now recognized as the principal effectors of this form of regulated cell death; activated gasdermins insert into cell membranes, where they form pores that result in the secretion of cytokines, alarmins and damage-associated molecular patterns and cause cell membrane rupture. It is now evident that gasdermins can be activated by inflammasome- and caspase-independent mechanisms in multiple cell types and that crosstalk occurs between pyroptosis and other cell death pathways. Although they are important for host antimicrobial defence, a growing body of evidence supports the notion that pyroptosis and gasdermins have pathological roles in cancer and several non-microbial diseases involving the gut, liver and skin. The well-documented roles of inflammasome activity and apoptosis pathways in kidney diseases suggests that gasdermins and pyroptosis may also be involved to some extent. However, despite some evidence for involvement of pyroptosis in the context of acute kidney injury and chronic kidney disease, our understanding of gasdermin biology and pyroptosis in the kidney remains limited.

Resolution of the Council of Excperts (16th June, 2022): Therapy of gouty arthritis with an IL-1 inhibitor (anakinra)

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Hypoxic human proximal tubular epithelial cells undergo ferroptosis and elicit an NLRP3 inflammasome response in CD1c+ dendritic cells

Inflammasomes are multiprotein platforms responsible for the release of pro-inflammatory cytokines interleukin (IL)-1β and IL-18. Mouse studies have identified inflammasome activation within dendritic cells (DC) as pivotal for driving tubulointerstitial fibrosis and inflammation, the hallmarks of chronic kidney disease (CKD). However, translation of this work to human CKD remains limited. Here, we examined the complex tubular cell death pathways mediating inflammasome activation in human kidney DC and, thus, CKD progression. Ex vivo patient-derived proximal tubular epithelial cells (PTEC) cultured under hypoxic (1% O₂) conditions modelling the CKD microenvironment showed characteristics of ferroptotic cell death, including mitochondrial dysfunction, reductions in the lipid repair enzyme glutathione peroxidase 4 (GPX4) and increases in lipid peroxidation by-product 4-hydroxynonenal (4-HNE) compared with normoxic PTEC. The addition of ferroptosis inhibitor, ferrostatin-1, significantly reduced hypoxic PTEC death. Human CD1c⁺ DC activated in the presence of hypoxic PTEC displayed significantly increased production of inflammasome-dependent cytokines IL-1β and IL-18. Treatment of co-cultures with VX-765 (caspase-1/4 inhibitor) and MCC950 (NLRP3 inflammasome inhibitor) significantly attenuated IL-1β/IL-18 levels, supporting an NLRP3 inflammasome-dependent DC response. In line with these in vitro findings, in situ immunolabelling of human fibrotic kidney tissue revealed a significant accumulation of tubulointerstitial CD1c⁺ DC containing active inflammasome (ASC) specks adjacent to ferroptotic PTEC. These data establish ferroptosis as the primary pattern of PTEC necrosis under the hypoxic conditions of CKD. Moreover, this study identifies NLRP3 inflammasome signalling driven by complex tubulointerstitial PTEC-DC interactions as a key checkpoint for therapeutic targeting in human CKD.

Novel insights into NOD-like receptors in renal diseases

Nucleotide-binding oligomerization domain-like receptors (NLRs), including NLRAs, NLRBs (also known as NAIPs), NLRCs, and NLRPs, are a major subfamily of pattern recognition receptors (PRRs). Owing to a recent surge in research, NLRs have gained considerable attention due to their involvement in mediating the innate immune response and perpetuating inflammatory pathways, which is a central phenomenon in the pathogenesis of multiple diseases, including renal diseases. NLRs are expressed in different renal tissues during pathological conditions, which suggest that these receptors play roles in acute kidney injury, obstructive nephropathy, diabetic nephropathy, IgA nephropathy, lupus nephritis, crystal nephropathy, uric acid nephropathy, and renal cell carcinoma, among others. This review summarises recent progress on the functions of NLRs and their mechanisms in the pathophysiological processes of different types of renal diseases to help us better understand the role of NLRs in the kidney and provide a theoretical basis for NLR-targeted therapy for renal diseases.

The use of anti-interleukin-1 agents and tumor necrosis factor-alpha inhibitors in renal transplant recipients

Objectives

The aim of this study was to investigate the efficacy and safety of anti-interleukin-1 (anti-IL-1) agents and tumor necrosis factor-alpha (TNF-α) inhibitors in renal transplant patients.

Patients and methods

Between February 2014 and February 2020, data of 12 renal transplant recipients (9 males, 3 females; median age: 51 years; range, 19 to 70 years) who received anti-IL-1 agents or TNF-α inhibitors for inflammatory diseases in the post-transplant time period and were followed in a single transplant center (n=12) were retrospectively analyzed. A total of 46 cases were reported in the literature, before the data were collected. The overall outcomes of all cases were analyzed in this study.

Results

Thirty-seven patients received anti-IL-1 agents in the post-transplant period. The main indications for anti-IL-1 agents were familial Mediterranean fever (FMF) and amyloidosis (75.7%). The continuation rate of colchicine treatment in patients with FMF was 85.7%. Anti-IL-1 agents prevented attacks completely in 89.3% of FMF patients. The number of cases used TNF-α inhibitors among renal transplant patients was lower (n=21). The TNF-α inhibitors were used mainly for inflammatory bowel diseases (57.1%) and ankylosing spondylitis (33.3%) and suppressed the disease activity in most of the patients with inflammatory diseases (72.7%). Death (n=3) and malignancies (n=3) were reported in patients who received TNF-α inhibitors, but not in patients who received anti-IL-1. The renal outcomes and graft survival rates were satisfactory in patients who received both anti-IL-1 agents and TNF-α inhibitors.

Conclusion

Our results support that anti-IL-1 agents can be used effectively and safely in renal transplant patients.

Features and Outcomes of Microcrystalline Arthritis Treated by Biologics: A Retrospective Study

OBJECTIVES

The usual treatments for crystal-associated arthritis are sometimes contraindicated; thus, new therapies against interleukin-1beta (IL-1) have been developed. We evaluated the characteristics of patients who received biological treatment for crystal-associated arthritis.

PATIENTS AND METHODS

We conducted a multicentric retrospective observational study in six rheumatology units in western France. Patients receiving a biological treatment for crystal-associated arthritis between 1 January 2010 and 31 December 2018 were included. Improvement was defined as at least a 50% decrease in the count of synovitis and C-reactive protein level.

RESULTS

Forty-six patients were included: 31 (67.4%) were treated for gouty arthritis, and 15 (32.6%) for calcium pyrophosphate crystal deposition disease (CCPD). The first biotherapy used was anakinra for 14 patients (93.3%) with CCPD and 31 patients (100.0%) with gout. The first biotherapy course was more efficient in treating gout than in treating CCPD, with success in 28 patients (90.3%) and 5 patients (35.7%), respectively (p = 0.001). Six patients (42.9%) with CCPD stopped their first biotherapy course because of side effects. Among the patients with gout, urate-lowering therapy was more frequently used after (100%) than before the first biotherapy course (67.7%) (p = 0.002).

CONCLUSION

Anakinra was prescribed for cases of refractory crystal-associated arthritis or cases with contraindications for usual treatments. The efficacy of anakinra in treating CCPD was not obvious. Patients with CCPD had more side effects. The biotherapy was introduced with a long-term objective, while anti-IL-1 therapies are approved for acute crises only.

Efficacy and safety of gout flare prophylaxis and therapy use in people with chronic kidney disease: a Gout, Hyperuricemia and Crystal-Associated Disease Network (G-CAN)-initiated literature review

Gout flare prophylaxis and therapy use in people with underlying chronic kidney disease (CKD) is challenging, given limited treatment options and risk of worsening renal function with inappropriate treatment dosing. This literature review aimed to describe the current literature on the efficacy and safety of gout flare prophylaxis and therapy use in people with CKD stages 3-5. A literature search via PubMed, the Cochrane Library, and EMBASE was performed from 1 January 1959 to 31 January 2018. Inclusion criteria were studies with people with gout and renal impairment (i.e. estimated glomerular filtration rate (eGFR) or creatinine clearance (CrCl) < 60 ml/min/1.73 m²), and with exposure to colchicine, interleukin-1 inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), and glucocorticoids. All study designs were included. A total of 33 studies with efficacy and/or safety analysis stratified by renal function were reviewed-colchicine (n = 20), anakinra (n = 7), canakinumab (n = 1), NSAIDs (n = 3), and glucocorticoids (n = 2). A total of 58 studies reported these primary outcomes without renal function stratification-colchicine (n = 29), anakinra (n = 10), canakinumab (n = 6), rilonacept (n = 2), NSAIDs (n = 1), and glucocorticoids (n = 10). Most clinical trials excluded study participants with severe CKD (i.e. eGFR or CrCl of < 30 mL/min/1.73 m²). Information on the efficacy and safety outcomes of gout flare prophylaxis and therapy use stratified by renal function is lacking. Clinical trial results cannot be extrapolated for those with advanced CKD. Where possible, current and future gout flare studies should include patients with CKD and with study outcomes reported based on renal function and using standardised gout flare definition.

Off-label use of anti-IL-1 drugs in rheumatic diseases

Interleukin-1 (IL-1) plays a key role in the pathogenesis of different rheumatic diseases. There are now several agents available on the market capable of blocking IL-1. The proven effectiveness and excellent safety of these drugs makes them a possible therapeutic option in the treatment of IL-1 driven diseases, when previous therapies are contraindicated or ineffective. This article discusses the European wide off-label use of these drugs for the treatment of rheumatic diseases.

Use of Anti-Cytokine Therapy in Kidney Transplant Recipients with COVID-19

In the context of the coronavirus disease 2019 (COVID-19) pandemic, we aimed to evaluate the impact of anti-cytokine therapies (AT) in kidney transplant recipients requiring hospitalization due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This is an observational retrospective study, which included patients from March to May 2020. An inverse probability of treatment weighting from a propensity score to receive AT was used in all statistical analyses, and we applied a bootstrap procedure in order to calculate an estimation of the 2.5th and 97.5th percentiles of odds ratio (OR). outcomes were measured using an ordinal scale determination (OSD). A total of 33 kidney recipients required hospitalization and 54% of them received at least one AT, mainly tocilizumab (42%), followed by anakinra (12%). There was no statistical effect in terms of intensive care unit (ICU) admission, respiratory secondary infections (35% vs. 7%) or mortality (16% vs. 13%) comparing patients that received AT with those who did not. Nevertheless, patients who received AT presented better outcomes during hospitalization in terms of OSD ≥5 ((OR 0.31; 2.5th, 97.5th percentiles (0.10; 0.72)). These analyses indicate, as a plausible hypothesis, that the use of AT in kidney transplant recipients presenting with COVID-19 could be beneficial, even though multicenter randomized control trials using these therapies in transplanted patients are needed.

The Management of Gout in Renal Disease

Gout, a debilitating inflammatory arthritis, currently affects more than 9 million Americans. Hyperuricemia, the laboratory abnormality associated with the development of gout, also occurs in a significant number of patients with chronic kidney disease (CKD), a condition that affects approximately 14% of the US population. Several recent studies have attempted to provide a definitive link between the presence of hyperuricemia and progression of CKD; however, the treatment of asymptomatic hyperuricemia in CKD is not supported by recent randomized controlled trials. The pharmacology of acute gout flares and urate lowering is complicated in patients who also have evidence of CKD, primarily because of an increased risk of medication toxicity. Recipients of kidney transplants are particularly at risk of debilitating gout and medication toxicity. We review the available data linking CKD, gout, and hyperuricemia, providing practice guidelines on managing gout in CKD patients and kidney transplant recipients. We advocate for much greater involvement of nephrologists in the management of gout in renal patients.

2020 Recommendations from the French Society of Rheumatology for the management of gout: Management of acute flares

OBJECTIVE

To develop French Society of Rheumatology-endorsed recommendations for the management of gout flares.

METHODS

These evidence-based recommendations were developed by 9 rheumatologists (academic or community-based), 3 general practitioners, 1 cardiologist, 1 nephrologist and 1 patient, using a systematic literature search, one physical meeting to draft recommendations and 2 Delphi rounds to finalize them.

RESULTS

A set of 4 overarching principles and 4 recommendations was elaborated. The overarching principles emphasize the importance of patient education, including the need to auto-medicate for gout flares as early as possible, if possible within the first 12h after the onset, according to a pre-defined treatment. Patients must know that gout is a chronic disease, often requiring urate-lowering therapy in addition to flare treatment. Comorbidities and the risk of drug interaction should be screened carefully in every patient as they may contraindicate some anti-inflammatory treatments. Colchicine must be early prescribed at the following dosage: 1mg then 0.5mg one hour later, followed by 0.5mg,2 to 3 times/day over the next days. In case of diarrhea, which is the first symptom of colchicine poisoning, dosage must be reduced. Colchicine dosage must also be reduced in patients with chronic kidney disease or taking drugs, which interfere with its metabolism. Other first-line treatment options are systemic/intra-articular corticosteroids, or non-steroidal anti-inflammatory agents (NSAIDs). IL-1 inhibitors can be considered as a second-line option in case of failure, intolerance or contraindication to colchicine, corticosteroids and NSAIDs. They are contraindicated in cases of infection and neutrophil blood count should be monitored.

CONCLUSION

These recommendations aim to provide strategies for the safe use of anti-inflammatory agents, in order to improve the management of gout flares.

The role of inflammasomes in kidney disease

Inflammasomes are multiprotein innate immune complexes that regulate caspase-dependent inflammation and cell death. Pattern recognition receptors, such as nucleotide-binding oligomerization domain (NOD)-like receptors and absent in melanoma 2 (AIM2)-like receptors, sense danger signals or cellular events to activate canonical inflammasomes, resulting in caspase 1 activation, pyroptosis and the secretion of IL-1β and IL-18. Non-canonical inflammasomes can be activated by intracellular lipopolysaccharides, toxins and some cell signalling pathways. These inflammasomes regulate the activation of alternative caspases (caspase 4, caspase 5, caspase 11 and caspase 8) that lead to pyroptosis, apoptosis and the regulation of other cellular pathways. Many inflammasome-related genes and proteins have been implicated in animal models of kidney disease. In particular, the NLRP3 (NOD-, LRR- and pyrin domain-containing 3) inflammasome has been shown to contribute to a wide range of acute and chronic microbial and non-microbial kidney diseases via canonical and non-canonical mechanisms that regulate inflammation, pyroptosis, apoptosis and fibrosis. In patients with chronic kidney disease, immunomodulation therapies targeting IL-1β such as canakinumab have been shown to prevent cardiovascular events. Moreover, findings in experimental models of kidney disease suggest that small-molecule inhibitors targeting NLRP3 and other inflammasome components are promising therapeutic agents.

Patients Prescribed Anakinra for Acute Gout Have Baseline Increased Burden of Hyperuricemia, Tophi, and Comorbidities, and Ultimate All-Cause Mortality

Objective:

The interleukin-1 (IL-1) receptor antagonist anakinra is an effective, off-label option in acute gout flares, when conventional therapy options are narrowed. We performed a retrospective, randomized, case-controlled study to gain clinical insight on baseline factors for gout patients most likely to receive anakinra, and ultimate mortality of those who received anakinra.

Methods:

Of 1451 gout patients seen between January 2003 and January 2015 in a Veterans Affairs (VA) rheumatology group practice, under stringent managed care principles, 13 (100% male), who received anakinra at least once for flares, were compared with 1:4 age- and sex-matched gout controls. Each patient’s first rheumatology encounter was studied by factor analysis for variables associated with later anakinra.

Results:

At baseline, patients that received anakinra had higher urate burden (palpable tophi [10/13] vs controls [16/52], P = .003), serum urate ([10.6 mg/dL] vs controls [7.6 mg/dL], P < .0001), and East Asian descent ([7/13] vs [16/52], P = .041). The anakinra group had higher ultimate all-cause mortality ([6/13] vs controls [7/52], relative risk [RR] = 3.43, 95% confidence interval [CI] = 1.39-8.48, P = .0076). Factor analysis showed baseline visit palpable tophus and statin use to be most strongly associated with later anakinra use. Increased mortality of anakinra users, as per a factorial analysis, was linked more strongly to comorbidities than to anakinra.

Conclusions:

At baseline rheumatology gout encounter, higher urate, palpable tophi, statin prescription, and East Asian descent were associated with later anakinra use for flares. Mortality was more closely associated to the presence of comorbidities at baseline rheumatology visit than to anakinra prescription.

Difficult-to-treat gout flares: eligibility for interleukin-1 inhibition in private practice is uncommon according to current EMA approval

Objective

The objective was to determine the proportion of patients with difficult-to-treat or difficult-to-prevent acute gout attacks eligible for IL-1 inhibition.

Methods

Participants included in the French cross-sectional GOSPEL cohort (n = 1003 gout patients) were examined for contraindications and intolerance to standard of care (SoC) drugs of gout flares (colchicine, non-steroidal anti-inflammatory drugs and systemic glucocorticoids). Patients were classified as definitely eligible for first-line IL-1 inhibition (canakinumab) according to European summary of product characteristics (contraindications/intolerance to SoC and at least three flares per year) without any other anti-inflammatory options (contraindications/intolerance only), or potentially eligible (precaution of use). Eligibility to receive IL-1 during an on-going flare related to insufficient efficacy was assessed (second-line eligibility).

Results

Definite first-line eligibility for IL-1 therapy was found in 10 patients (1%) and contraindication to all SoC therapies in nine patients who had presented <3 flares in the past 12 months. At least precaution of use for SoC therapies was noted for 218/1003 patients (21.7%). Of 487 patients experiencing flares at baseline, 114 (23.4%) were still experiencing pain scored ⩾4/10 numeric scale on day 3, one of whom could not receive further SoC drugs. Only nine of them had three or more flares in the past year and were eligible for second-line IL-1 inhibition.

Conclusion

Despite significant numbers of patients without any SoC anti-inflammatory therapeutic options for gout flares, eligibility for IL-1 inhibition therapy according to current European approval is rare.

Use of Anakinra in Hospitalized Patients with Crystal-associated Arthritis

OBJECTIVE

In this retrospective observational study, we assess the efficacy and safety of the interleukin 1 receptor antagonist anakinra in medically complex, hospitalized patients with acute gout and calcium pyrophosphate crystal arthritis.

METHODS

Adult inpatients treated with anakinra from 2014 to 2017 were identified for inclusion. Charts were reviewed for demographics, comorbidities, laboratory data, pain scores, joint involvement, prior treatment, dosing and response to anakinra, concurrent infections, and surgical interventions. Response to anakinra treatment was determined from review of provider documentation, as well as recorded pain scores on a numeric scale.

RESULTS

We identified 100 individuals accounting for 115 episodes of arthritis. This population was 82% male, with an average age of 60 years. Comorbidities included renal disease (45%) and history of organ transplantation (14%). Twenty-nine episodes of arthritis occurred in the perioperative setting. Concurrent infection was present in 34 episodes. Eighty-six episodes of arthritis had partial or complete response to anakinra within 4 days of treatment initiation; 66 episodes had partial or complete response within 1 day of anakinra administration. Anakinra was well tolerated.

CONCLUSION

To our knowledge, this is the largest observational study of anakinra use in the inpatient setting for the acute treatment of crystal-associated arthritis. We observed a rapid response to anakinra, with 75% of episodes significantly improving or completely resolving within 4 days of the first dose. Our data also support the use of this biologic agent in individuals with infections, as well as perioperative individuals and immunosuppressed transplant recipients.

Anakinra for the treatment of acute gout flares: a randomized, double-blind, placebo-controlled, active-comparator, non-inferiority trial

OBJECTIVES

To evaluate the efficacy and safety of anakinra in treating acute gout flares in a randomized, double-blind, placebo-controlled, active comparator, non-inferiority (NI) trial.

METHODS

Patients with a crystal-proven acute gout flare were randomized (1: 1) to treatment with anakinra or treatment as usual (free choice: either colchicine, naproxen or prednisone). The primary end point was the change in pain between baseline and the averaged pain score on days 2-4 measured on a five-point rating scale. NI of anakinra would be established if the upper bound of the 95% CI of the numeric difference in changed pain scores between treatment groups did not exceed the NI limit of 0.4 in favour of treatment as usual, in the per-protocol (PP) and intention-to-treat (ITT) populations, assessed in an analysis of covariance model. Secondary outcomes included safety assessments, improvement in pain, swelling, tenderness and treatment response after 5 days, assessed using linear mixed models and binary logistic regression models.

RESULTS

Forty-three patients received anakinra and 45 treatment as usual. Anakinra was non-inferior (mean difference; 95% CI) to treatment as usual in both the PP (-0.13; -0.44, 0.18) and ITT (-0.18; -0.44, 0.08) populations. No unexpected or uncommon (serious) adverse events were observed in either treatment arm. Analyses of secondary outcomes showed that patients in both groups reported similar significant reductions in their gout symptoms.

CONCLUSION

Efficacy of anakinra was shown to be non-inferior to treatment as usual for the treatment of acute gout flares, suggesting that anakinra is an effective treatment alternative for acute gout flares.

TRIAL REGISTRATION

Het Nederlands Trial Register, www.trialregister.nl, NTR5234.